Upgrading ZFS Storage Pools

If you have ZFS storage pools from a previous Solaris release, such
as the Solaris 10 6/06 release, you can upgrade your pools with the zpool
upgrade command to take advantage of the pool features in the current
release. In addition, the zpool status command has been
modified to notify you when your pools are running older versions. For example:

# zpool status
pool: test
state: ONLINE
status: The pool is formatted using an older on-disk format. The pool can
still be used, but some features are unavailable.
action: Upgrade the pool using 'zpool upgrade'. Once this is done, the
pool will no longer be accessible on older software versions.
scrub: none requested
config:
NAME STATE READ WRITE CKSUM
test ONLINE 0 0 0
c1t27d0 ONLINE 0 0 0
errors: No known data errors

You can use the following syntax to identify additional information
about a particular version and supported releases.